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Speaker sensitivity

Can someone explain speaker sensitivity in layman's terms please. e.g. is a speaker of sensitivity 89 dB more or less sensitive than one of 90 dB? Also, does it work that more sensitive speakers reach their optimum/most pleasing output state at a lower volume?

My holy grail (due to a 2 year old daughter) is speakers that sound very good at low volumes.

P.S. My current system is NAD 352 amp, Nad 542 CDP, AE Aelite 2 apeakers (I also have Wharfedale 9.1s and Eltax Monitor 3's for tinkering purposes.

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Re: Speaker sensitivity

hello kev,the higher the sensitivity the easier it is to drive a speaker so you can listen at a lower volume with the same wattage amp.i use a ten watt valve amp with speakers with a sensitivity rating of 94db any lesser then the amp would struggle to drive the speakers efficiently.an 89 db speaker is fairly high with the average about 87db.as for the optimun listening level a bit of volume never hurt anyone but with more sensitive speakers then listening at moderate levels with a 20 watt amp will sound louder than a lower figure speaker.ohm resistance plays its part as well with most speakers around the 8 ohm figure sometimes dipping to 5 ohms or less so most amplifier makers cater for these dips and troughs by having a 4 to 8 ohm tap especially with valve amps.so if a speaker has an ohm figure of say 6 then most amps can cope with this figure.i hope this helps.all the best,gregory.

Anonymous
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Re: Speaker sensitivity

In crude terms, sensitivity tells how loud a speaker will play on a
certain power rating. The higher the sensitivity, the louder it will
play given the same power.

A loudspeaker that is said to have a
sensitivity of 89, will produce 89 dB at a distance of 1 meter away
from it, given 1 watt of power.

That said, it seems higher the
sensitivity, the better the speaker. It generally is true, but not
always. Many people will sacrifice on sensitivity to gain on other
parameters. And keeping in mind your NAD C-352, which is 2 x 80W Continuous Power into 4 / 8 ohms and 115W, 185W, 240W IHF Dynamic Power into 8, 4 and 2 ohms,
you don't really need to worry about the sensitivity. Anything above 88
dB is good, really. (Specially because you don't need to go 110 dB).

Keeping in mind your holy grail, you need speakers that offer a great dynamic range, sensitivity ain't that important for you.

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Re: Speaker sensitivity

user="ranjeetrain" wrote:
In crude terms, sensitivity tells how loud a speaker will play on a certain
power rating.

I disagree! Most of my (old and current) speakers rates around 4 ohms/86 dB (some was 84dB) and they all awesomely good.

Anonymous
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Re: Speaker sensitivity

user="Thaiman" wrote:
Most of my (old and current) speakers rates
around 4 ohms/86 dB (some was 84dB) and they all awesomely good.

I
agree. Sensitivity has nothing to do with sound quality. If sensitivity
were a scale of quality everyoen will buy speakers with 94 dB and all
amp manufacturers would have to stop worry about amps above 100
wrms/channel.

It is physics. Let me see if I can explain.

::: For a speaker with 87 dB sensitivity :::

Produces 87 dB of acoustic energy given   1 watt of power

Produces 90 dB of acoustic energy given   2 watts of power

Produces 93 dB of acoustic energy given   4 watts of power

Produces 96 dB of acoustic energy given   8 watts of power

Produces 99 dB of acoustic energy given  16 watts of power

Produces 102 dB of acoustic energy given 32 watts of power

Produces 105 dB of acoustic energy given 64 watts of power

Produces 108 dB of acoustic energy given 128 watts of power

Produces 111 dB of acoustic energy given 256 watts of power

Conclusion: With a loudspeaker with sensitivity of 87 dB, to
produce acoustic energy equivalent of 111 dB you need 256 wrms of power
(exempt the loudspeaker load for the sake of simplicity)

 

::: Now for a speaker with 94 dB sensitivity :::

Produces 94 dB of acoustic energy given   1 watt of power

Produces 97 dB of acoustic energy given   2 watts of power

Produces 100 dB of acoustic energy given   4 watts of power

Produces 103 dB of acoustic energy given   8 watts of power

Produces 106 dB of acoustic energy given  16 watts of power

Produces 109 dB of acoustic energy given 32 watts of power

Produces 112 dB of acoustic energy given 64 watts of power

Conclusion: With a loudspeaker with sensitivity of 94 dB, you can
produce a louder sound (112 dB) just with an amp offering 64 wrms.

See the difference? The difference is in efficiency my friend, not sound quality.

 

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Re: Speaker sensitivity

Good post Ranj, Also consider that most of "good" amp will double the power when ohms drop by half therefore, generally speaking, the 4-6 ohms speakers should have a better Dynamic range than the 8 ohms pair.

Anonymous
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Re: Speaker sensitivity

user="Thaiman" wrote:
Good post Ranj, Also consider that most of "good" amp will double the power when ohms drop by half therefore, generally speaking, the 4-6 ohms speakers should have a better Dynamic range than the 8 ohms pair.
 

Correct! Most audiophiles would prefer a 84 dB / 4 Ohms speaker over a 94 dB 8 Ohms speaker. And probably they can afford to, because their gear can drive them well. Most listeners have amps that produce less than 100 wrms continuously, hence the desire of bettering the sensitivity rating.

Anonymous
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Re: Speaker sensitivity

So, in essence, I should ignore sensitivity figures except for the extremes. If I want to get a speaker/amp combination that sounds good at low volumes (and still sounds good at high volumes cos of course there are certain times when I get the chance to do this) I will have to listen to several setups by trawling around the local hi fi shops. Oh what a nightmare Wink

 Also when looking for a speaker with a good dynamic range I should look for 4-6 ohms impedence?

Anonymous
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Re: Speaker sensitivity

user="kevjones" wrote:
Also when looking for a speaker with a good dynamic range I should look for 4-6 ohms impedence?

Generally speaking, that would be correct. But Dynamic Range of final output is not a direct function of speaker impedence. You can find plenty of 8 ohm speakers that will produce a better dynamic range than many low impedence loudspeaker. Important thing to keep in mind is the output impedence of your amp. Speaker impedence should match with them. Generally, 8 ohm outputs can also take 6/4 ohm loads, but if one is thinking in pure terms, speaker impedence should match the amp output impedence.

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